fix fds loading

src/driver.h

@@ -188,9 +188,13 @@ int FCEUI_SetCheat(uint32 which, const char *name, int32 a, int32 v, int compare
 void FCEUI_CheatSearchShowExcluded(void);
 void FCEUI_CheatSearchSetCurrentAsOriginal(void);
 
+//.rom
 #define FCEUIOD_ROMS    0
+//NV = nonvolatile. save data.
 #define FCEUIOD_NV      1
+//savestates
 #define FCEUIOD_STATES  2
+//.fds ?
 #define FCEUIOD_FDSROM  3
 #define FCEUIOD_SNAPS   4
 #define FCEUIOD_CHEATS  5

src/drivers/win/archive.cpp

@@ -401,6 +401,8 @@ ArchiveScanRecord FCEUD_ScanArchive(std::string fname)
 
 	//check the file against the signatures
 	std::fstream* inf = FCEUD_UTF8_fstream(fname,"rb");
+	if(!inf) return ArchiveScanRecord();
+
 	int matchingFormat = -1;
 	for(uint32 i=0;i<(int)formatRecords.size();i++)
 	{

src/drivers/win/main.cpp

@@ -1188,7 +1188,11 @@ std::fstream* FCEUD_UTF8_fstream(const char *n, const char *m)
 	else if(!strcmp(m,"a+") || !strcmp(m,"a+b"))
 		mode |= std::ios_base::in | std::ios_base::out | std::ios_base::app;
 	
-	return new std::fstream(n,mode);
+	std::fstream *fs = new std::fstream(n,mode);
+	if(!fs->is_open()) {
+		delete fs;
+		return 0;
+	} else return fs;
 }
 
 FILE *FCEUD_UTF8fopen(const char *n, const char *m)